Nonspecific immunity depends on a newly infected animal's previous exposure to the same pathogen.

utilizes highly specific antigen receptors on B cells.

is based on recognition of antigens that are specific to different pathogens.

is activated immediately upon infection.

Many archeologists and anthropologists disagree with dr. thorne's view.  thorne strongly believes that what many calls "homo erectus"  was in fact  homo sapiens,  and that they migrated out of africa almost 2 million years ago and dispersed throughout europe and asia. that's way different  from what scientists have always believed about the evolution of the species.